The present invention relates to a beverage dispensing apparatus for dispensing premixed beverages from a single beverage dispensing head, the premixed beverages being supplied to the head through a number of hoses each connected to the respective individual premixed beverage sources.
Hand-held beverage dispensers provide the operator with the ability to dispense several different types of beverages from a single hand-held beverage dispensing head. Hand-held beverage dispensers are very popular for use in bars, where a bartender is frequently required to quickly and efficiently dispense a large number of beverages. By using a hand-held beverage dispenser, a bartender can dispense several types of beverages from a single dispenser head merely by pushing a different button corresponding to the desired beverage.
Hand-held beverage dispensers generally fall into two categories: premixed beverage dispensers and postmixed beverage dispensers. Postmixed beverage dispensers dispense beverages from a single beverage dispensing head by mixing soda water and syrup in the dispenser head. An example of such a beverage dispensing apparatus is shown in U.S. Pat. No. 4,619,378 to de Man. This patent discloses an apparatus for dispensing beverages from a pressurized source of syrup and soda to be mixed in and discharged from a beverage dispensing head. Premixed dispensing devices dispense premixed beverages directly from the beverage supply. No mixing is required prior to dispensing, as is the case in postmixed beverage dispensers. An example of a premixed beverage dispensing system is shown in U.S. Pat. No. 3,216,445 to Cornelius. The Cornelius beverage dispenser dispenses premixed carbonated beverages through a dispenser head which is connected to supply conduits running to the individual premixed beverage supplies. Both premixed and postmixed beverage supplies are in widespread application.
Since premixed beverage dispensers are primarily used to dispense carbonated beverages, effervescent foam generated upon the dispensing of the beverage presents a problem. Generation of excessive foam upon dispensing of the beverage is inefficient and annoying since the operator must stop dispensing the beverage so as to allow the foam to subside. The foam is created by turbulence in the flow of the carbonated beverage through the dispenser channel. In postmixed dispensers this turbulence is desirable since the turbulent churning of syrup and soda water mixes the beverage as it passes through the dispenser head. In premixed dispensers, however, it is desirable to reduce, or eliminate altogether, turbulent flow, so that the amount of foam generated is minimal. Turbulent flow is typically created in prior art beverage dispensers by perpendicular or essentially perpendicular changes in the direction of flow as the beverage traverses the channel through the beverage head. Thus, it is highly desirable to eliminate wherever possible abrupt angular changes of flow direction in order to minimize foaming of the dispensed beverage.
Indeed, postmixed prior art dispensers such as those shown in U.S. Pat. No. 4,497,421 to Schilling, U.S. Pat. No. 4,619,378 to Giampa, and the patent to de Man, noted above, all show dispenser heads having abrupt angular changes in flow direction. Of course, since these three references teach postmixed dispensers, the creation of turbulent flow within the dispenser head is a desirable object for reasons already discussed. However, none of the dispensers would perform satisfactorily as premixed dispensers. The abrupt perpendicular changes in the direction of flow would create substantial turbulence and generate an unacceptable amount of foam.
An existing premixed beverage dispenser such as the dispenser shown in the patent to Cornelius realizes the problem of reducing the number of abrupt angular changes in order to minimize foaming. However, in order to reduce such abrupt angular changes in flow direction, the Cornelius apparatus locates the valve actuating buttons so that the buttons are axially coincident with the valve poppets. This design is exceptionally awkward since the operator is required to "reach over" the dispenser head with his forefinger in order to press the appropriate dispenser button. It would be more desirable to place the buttons in a location on the dispenser head more conveniently proximate to the operator's fingers.
Turbulent flow is also created in the prior art by incidence of the beverage over the surface of conventional valve poppets when the valve is opened and the beverage is dispensed. Conventional poppets include an O-ring groove which is machined or molded about circumference of the poppet. In order to accommodate dimensional tolerances of the o-rings and provide for efficient loading, the o-ring groove is machined or molded wider than the cross-sectional diameter of the o-ring. As a result, gaps exist on either side of the o-rings which disrupt the otherwise smooth surface of the poppet. These discontinuities along the surface of the poppet create localized turbulent regions along the flow path of the beverage and result in foaming of the beverage as the beverage is dispensed.
Another problem with existing premixed dispensers is the difficulty and inconvenience encountered in servicing the valve seal of the individual valve elements in the beverage dispenser head. Most premixed beverage dispensers contain several channels having individual valves for each channel which control the flow of beverages in that channel. With repeated use, the seals on the valves degenerate and the seal becomes insecure, resulting in the beverages leaking out of the dispenser head. Periodic maintenance of the valve seals maintains the integrity of the valve seal. This maintenance consists principally of replacing the o-rings on the individual valve poppets. Existing valve poppets are typically of unitary construction having a circumferential groove which accommodates an o-ring. Further, to replace the o-ring, the old o-ring is removed and a replacement o-ring is rolled over the length of the poppet and seated in the groove. This conventional loading technique can result in the o-rings being seated "inside out" in the groove as a result of being rolled over the length of the poppet. The resulting distortion presents a potential for aggravating the foaming problem.